Hearing aid construction



1965 J. DE GROOT ETAL HEARING AID CONSTRUCTION Filed Nov. 23, 1962 FIGJ.

FIG.2 5s 45 4 INVENTOR JACOB DE GROOT JOHANNES MBJLKAANDERS United States Patent 3,221,111 HEARING AID CONSTRUCTION Jacob de Groot and Johannes Matheus Gerardus Maria Kaanders, Emmasingel, Eindhoven, Netherlands, assignors to North American Philips Company, Inc., New York, N .Y., a corporation of Delaware Filed Nov. 23, 1962, Ser. No. 239,597 Claims priority, application Germany, Dec. 16, 1961,

N 13,260, N 13,261 3 Claims. (Cl. 179-107) The present invention relates to a hearing aid construction.

An object of the present invention is a hearing aid comprising a bipartite housing to be carried behind the ear, in which housing a receiver suspended in supporting brackets, a microphone, a battery housing and an amplifier are mounted on a chassis plate located in the housing.

In hearing aids of the conventional type the microphone and the receiver are constructed, each with its supporting bracket, in the form of a separate unit, which may be fastened in a separate compartment of the housing made from moulded material. This construction has the disadvantage that in the event that itis necessary to repair the hearing the various components interconnectcd by supply wires must be removed individually from the housing, which, of course, involves the risk of damage to the supply wires.

In accordance with the invention this disadvantage is overcome in that the battery housing and the two supporting brackets with the chassis plate are structurally integral with each other.

Another object of the present invention is the provision of a switch which occupies very little space in the hearing aid housing.

The switch according to the invention is characterized in that it comprises an insulating plate having contacts formed by surface-bound solderable metal layers lying side by side and a flat contact arm, which is rotatably journalled on the insulating plate by means of a flange tube depressed from a metal plate adhered to the insulating plate and which is in contact with one of the metal layers. The complete switch may have the appearance of a plate of, for example, 10 x 12 mm., the thickness being about 0.8 mm.

The invention will be described more fully with reference to the accompanying drawing, in which FIG. 1 is the hearing aid apparatus shown partially in a side elevation and partially in section.

FIG. 2 shows the apparatus of FIG. 1 in a rear elevation view, the rear half of the housing being removed,

FIG. 3 shows the apparatus in a perspective view, the housing being completely removed and FIG. 4 shows a perspective view of the switch of the invention.

The hearing aid shown comprises mainly a box shaped microphone 1, an amplifier 5 wtih volume control 7, a battery housing 9 with a battery 11 and a box-shaped receiver 13, these parts being housed in a curved, insulating housing 15 of moulded material. The housing 15 is bipartite and is separated along thecentral plane 17 (shown in broken lines in FIG. 1 following the curved shape of the housing) into two detachable parts which can be fastened to each other by means of a hook 19 formed at one of the halves, and a screw bolt 21. The shape and the dimensions of the housing 15 are such that it can be easily carried behind the ear in an approximately vertical position. A metal tube 23 is secured to the upper end (FIG. 1 the left-hand end) in the housing 15, said tube communicating by a flexible tube 25 with the outlet opening of the receiver 13 and with which, outside the housing 15, a tube (not shown) can 3,221,111 Patented Nov. 30, 1965 be connected, the free end of which provided with an ear piece can be disposed in the ear. An opening 27 is provided at the lower end (FIG. 1 the right-hand end) of the housing 15 which communicates through a flexible tube 29 with the inlet opening of the microphone 3.

The amplifier 5, which may comprise in a conventional manner of a number of transistors, resistors and capacitors is mounted on an insulating chassis plate 31, the chassis plate being provided on the bottom side thereof with surface wiring, preferably formed by metal layers, for example printed wiring. The flat chassis plate 31 extends parallel to the plane of symmetry of the housing 15 (in FIG. 1 parallel to the plane of the drawing) and follows, as far as the shape is concerned, the curvature of the housing 15.

The battery housing 9 is formed by a metal strip, bent over twice at right angles, the ends of which strip are fixed by means of tags bent around the chassis plate 31, for example, the tag 33 in FIG. 3, and/or by tags taken through suitable apertures of the chassis plate 31, and preferably bent over in the plate 31. The fastening tags or lugs are preferably fastened by soldering in a known manner to metal layers applied to the bottom side of the chassis plate 31, which layers may form part of the wiring, in which case an electrical connection to the metal battery housing 8 is established at the same time. The fourth wall of the battery housing 9, which is open on two .sides, is formed by part of the chassis plate 31. The latter is made from comparatively rigid material, for exmaple, hard paper, and thus results in a battery housing 9 made from very thin iron sheet which has sufficient rigidity that it can operate as a support for further parts. A substantially U-shaped metal bracket 35 is soldered to one of the side walls of the battery housing 9, at right angles to the chassis plate 31 (in the figures the left-hand side wall) and is provided with ends bent over at right angles (in the FIGS. 1 and 3 only one of the legs of the bracket is shown), this bracket supporting a receiver 13 by means of a rubber tape bent around the hook-like ends of the bracket 37. The volume control 7 is secured to the other side of the battery housing 9. Also the switch 39, shown in FIG. 4 and to be described more fully hereinafter, may be secured to said side wall.

The microphone 3 is secured by means of a rubber tape 41 similarly to the receiver 13, in a substantially 'Ushaped bracket 43, the bottom part of which is widened and elongated laterally by a piece 45, at the ends of which are formed fastening tags 47, taken through the chassis plate 31 and secured thereto by soldering (see FIG. 2), with the aid of which the supporting bracket 43 is secured to the chassis plate.

From the foregoing, it will appear that all electrical parts of the hearing aid are secured to the chassis plate 31, with which they are structurally integral, which unit can be removed, in the event of necessity of repairs, after the housing 15 has been opened and a nut securing the tube 23 in the housing has been loosened from the housing without the need for taking care that the connections between the parts of the apparatus should not be damaged.

The cylindrical battery 11 is accommodated in a suitable, substantially cup-shaped holder 49 of insulating material, in the bottom of which a small window (not visible in the figure) is provided, said holder being arranged in the battery housing 9 so as to be turned through a small angle and to be detachable. In the position shown in FIG. 2, a contact spring 51, fastened to the base plate 31, rests on the outer side of the bottom of the cup-shaped holder 49 and is insulated from the end face of the battery, forming one of the poles thereof and engaging the inner side of the bottom of the cup, whereas a tag 53, cut from the wall of the metal battery housing 9 and also serving as a contact spring engages the other end face of the battery 11, forming the other pole thereof. The connection between the battery and the amplifier 5 is thus interrupted; by a small turn of the holder 49 the window in the bottom thereof can be turned straight opposite the end of the contact spring 51, so that the apparatus is switched on.

If desired, the space between the battery housing 9 and the bracket 43 may be provided with a so-called listening coil 55 (shown only in FIG. 2 for the sake of clarity), which may be included in known manner instead of the microphone 3, in the input circuit of the amplifier 5, when the user of the apparatus has a telephone call. The switch 39 to be used for changing over preferably has the shape shown in FIG. 4 and consists of an insulating plate 57, for example, of hard paper, to which a two-armed lever 59, for example, of gold-plated thin sheet iron, is rotatably secured by means of a flanged tube 61. This flanged tube may be formed by a depression of a metal plate 63, which is glued to the bottom side of the insulating plate 57, and which serves at the same time as a stiffening member for the latter. One of the arms of the lever 59, as is shown in FIG. 4, and projects beyond the plate 57 and serves as a controlmember; the other arm constitutes a contact arm and co-operates with two surface-bound contacts 65 and 67, which are formed by surface-bound solderable metal layers arranged side by side on the surface of the plate 57, e.g. printed contacts while a third metal layer 69 is in contact with the lever 59. The connections with said metal plates can be directly soldered thereto. On the bottom side of the metal plate 63 there is provided a layer of an adhesive tape 71 having adhesive on both sides, by means of which the switch is adhered to the side wall of the battery housing 9, which also has the volume control 7, the adhesive tape serving at the same time as an insulation between the metal plate 63 and the metal side wall of the battery housing 9.

What we claim is:

1. A hearing aid construction comprising a bipartite housing adapted to be carried behind the wearers ear; a chassis plate in said housing; a microphone, an amplifier and a battery housing mounted on said chassis plate;

a receiver, a listening coil and a switch; said switch comprising an insulating plate having contacts formed by metal layers and by a flat contact arm, a flanged tube secured to said insulating plate for rotatably journaling said switch; an adhesive tape layer for securing said switch to a wall of said battery housing provided on both sides with an adhesive and forming an insulation therefor; a supporting bracket for said receiver, and a separate supporting bracket for said microphone; said supporting brackets and chassis plate forming a structural unit.

2. A hearing aid construction comprising a bipartite housing adapted to be carried behind the wearers ear; a chassis plate in said housing; a microphone, an amplifier, and a battery housing mounted on said chassis plate; a receiver, a U-shaped supporting bracket for said receiver secured by its bight portion to one of the side walls of said battery housing substantially perpendicular to the plane of said chassis plate, said receiver being suspended from said battery housing without being supported by said chassis plate; and a separate supporting bracket for said microphone; said supporting brackets and chassis plate forming a structural unit.

3. A hearing aid construction comprising a bipartite housing adapted to be carried behind the wearers ear; a chassis plate in said housing; a microphone, an amplifier and a battery housing mounted on said chassis plate; said battery housing being a substantially U-shaped metal strip having one of its free ends bent around the bottom of said chassis plate and secured thereto; a supporting bracket for said receiver, and a separate supporting bracket for said microphone; said supporting brackets and chassis plate forming a structural unit.

References Cited by the Examiner UNITED STATES PATENTS 2,530,621 11/1950 Lybarger 179-l07 2,742,537 4/1956 Leslie 200--6 2,794,080 5/1957 Stoecklin 2006 2,882,348 4/1959 Erickson 179107 3,102,172 8/1963 Cohen 179-107 3,123,678 3/1964 Prentiss et al 179107 ROBERT H. ROSE, Primary Examiner. 

1. A HEARING AID CONSTRUCTION COMPRISING A BIPARTITE HOUSING ADAPTED TO BE CARRIED BEHIND THE WEARER''S EAR; A CHASSIS PLATE IN SAID HOUSING; A MICROPHONE, AN AMPLIFIER AND A BATTERY HOUSING MOUNTED ON SAID CHASSIS PLATE; A RECEIVER, A LISTENING COIL AND A SWITCH; SAID SWITCH COMPRISING AN INSULATING PLATE HAVING CONTACTS FORMED BY METAL LAYERS AND BY A FLAT CONTACT ARM, A FLANGED TUBE SECURED TO SAID INSULATING PLATE FOR ROTATABLY JOURNALING SAID SWITCH; AN ADHESIVE TAPE LAYER FOR SECURING SAID SWITCH TO A WALL OF SAID BATTERY HOUSING PROVIDED ON BOTH SIDES WITH AN ADHESIVE AND FORMING AN INSULATION THEREFOR; A SUPPORTING BRACKET FOR SAID RECEIVER, AND A SEPARATE SUPPORTING BRACKET FOR SAID MICROPHONE; SAID SUPPORTING BRACKETS AND CHASSIS PLATE FORMING A STRUCTURAL UNIT. 